The presenter admitted that men appear nervous and frightened backstage because they fear facing a backlash from the ITV1 show's panellists.
In an interview with Take 5 magazine, McLean commented: "Goodness knows what they think we're going to do to them! It's the really blokey men who can't seem to handle it. They're usually shaking when they come on, with beads of sweat running down their foreheads.
"Only Russell Brand, Ricky Gervais and Alan Carr ever seemed completely at ease. But Enrique Iglesias was also a great guest. He was lovely and took the mickey out of himself."
In January, the show's second anchor Jackie Brambles revealed that male celebrities expect to be "ripped apart" on-air.
Speaking at the time, she insisted: "We try to put people at ease and have fun with the guests."